The Grinning Mask of Death

So there's a wave of zombie-themed computer and video games on the horizon. This naturally follows a recent wave of zombie movies. Why are the undead all the rage?

I have two complimentary theories that I'm going to discuss in this and the next blog entry. The first has to do with graphics and the second with the artificial intelligence (AI) that determines behavior. First, the visual aspect of the zombie craze.

Computer graphics have improved to the point where we can, fairly accurately, re-create human faces in 3D. The problem is, human beings are acutely aware of other human faces. We can read lips, sense small changes in expression, and most of us can remember a single face years amid thousands of others even after we've fogotten everything else about that indivdual. Millions of years of evolution and social pressure have hardwired facial recognition into the human brain. We're fine tuned for it. We subject the human face to such intense scrutiny that we can sense even the smallest infidelity.

The more something looks like a human face, the more these instincts kick in. While we forgive cartoons or caricatures, if a human-looking face rings false we react badly to it. Ironically, our quest for realism in computer graphics can actually make in-game characters seem less real. The problem is recognized in the robotics field, and has a name: the Uncanny Valley.

A good discussion of this phenomenon, and its relation to anthropomorphism, can be found in Dave Bryant's essay. In it, he considers primarily the visual aspects of the uncanny valley, but I'd like to argue that the uncanny valley is more than just visual; it also relates to motion and movement.

This is, after all, what makes acting an art and a discipline; it's not simply a matter of a human actor memorizing a bunch of lines and saying them on cue. An actor must get the body language right as well. The facial expression is the loudest part of that body language. Most audiences can tell when a smile is real or faked. It takes a really, really good actor to get the whole package -- his movement, voice and expression -- working together to fool the audience into thinking that they're looking at something real.

We can't do this in the computer world convincingly; at least not in real time. It requires teams of artists and animators to get the look. It requires a well-written script and a talented voice actor to get the sound. It requires a director who can put both these things together. It's really, really hard to get right.

What do you get if you get it wrong? Something unnatural and waxen. Something that doesn't look quite real, or quite alive. You get the undead. Enter the zombie game or movie. We see these characters because they are easy to do with current technology. It's easy to animate a stiffly moving character. If your computer-generated extras are going to walk like they have rigor mortis anyway, why not call them zombies?